This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We are interested in the structure and trafficking of lysosomal enzymes involved in disease. We have crystals of two proteins in this realm, each of which has proven to be refractory to structural studies using our in house Rigaku RU-HB300/Raxis IV++ x-ray facility as well as using beamlines X6A and X25 at Brookhaven. Thus, we would like to use the microfocus capabilities of the NECAT beamline at APS. Our crystals of one lysosomal protein diffract to 3.1 [unreadable] at Brookhaven beamline X6A, but have limited lifetime in the beam. Our needle-like crystals of a second lysosomal protein diffract to 4.2 [unreadable] at X6A, and we would like to improve their resolution in a microfocus beamline.